Problem: Baby Ehab was toying around with arrays. He has an array a of length n. He defines an array to be good if there's no way to partition it into 2 subsequences such that the sum of the elements in the first is equal to the sum of the elements in the second. Now he wants to remove the minimum number of elements in a so that it becomes a good array. Can you help him?

A sequence b is a subsequence of an array a if b can be obtained from a by deleting some (possibly zero or all) elements. A partitioning of an array is a way to divide it into 2 subsequences such that every element belongs to exactly one subsequence, so you must use all the elements, and you can't share any elements.

Input

The first line contains an integer n (2 ≤ n ≤ 100) — the length of the array a.

The second line contains n integers a_1, a_2, …, a_{n} (1 ≤ a_i ≤ 2000) — the elements of the array a.

Output

The first line should contain the minimum number of elements you need to remove.

The second line should contain the indices of the elements you're removing, separated by spaces.

We can show that an answer always exists. If there are multiple solutions, you can print any.

Examples

Input


4
6 3 9 12


Output


1
2

Input


2
1 2


Output


0

Note

In the first example, you can partition the array into [6,9] and [3,12], so you must remove at least 1 element. Removing 3 is sufficient.

In the second example, the array is already good, so you don't need to remove any elements.

Solution (in JAVA):

Solution:
import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;
import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;
import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Array;import java.lang.reflect.Field;import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;import java.security.AccessControlException;import java.util.Arrays;
import java.util.Collection;import java.util.Comparator;import java.util.List;import java.util.Map;
import java.util.Objects;import java.util.TreeMap;import java.util.function.Function;
import java.util.stream.Collectors;import java.util.stream.IntStream;import java.util.stream.LongStream;
import java.util.stream.Stream;public class _C {static public void main(final String[] args) 
throws IOException{C._main(args);}
static class C extends Solver{public C(){singleTest=true;}@Override public void solve()throws 
IOException{int n=sc.nextInt();sc.nextLine();int[]a=Arrays.stream(sc.nextLine().trim().split("\\s+")).filter($s2
->!$s2.isEmpty()).mapToInt(Integer::parseInt).toArray();int sum=Arrays.stream(a).sum();
if(sum%2==0){int sum1=sum/2;boolean[][]mat=new boolean[sum1+1][a.length+1];for(int 
i=0;i<mat[0].length;i++){mat[0][i]=true;}for(int i=1;i<mat.length;i++){mat[i][0]
=false;}for(int i=1;i<=sum1;i++){for(int j=1;j<=a.length;j++){if(i-a[j-1]>=0){mat[i][j]
=mat[i][j-1]|| mat[i-a[j-1]][j-1];}else{mat[i][j]=mat[i][j-1];}}}if(!mat[sum1][a.length])
{pw.println(0);}else{for(int i=0;i<n;i++){if(a[i]%2==1){pw.println(1);pw.println(i
+1);break;}int sum2=(sum-a[i])/2;if(!mat[sum2][a.length]){pw.println(1);pw.println(i
+1);break;}}}}else{pw.println(0);}}static public void _main(String[]args)throws IOException
{new C().run();}}static class Datas{static class Pair<K,V>{private K k;private V 
v;public Pair(final K t,final V u){this.k=t;this.v=u;}public K getKey(){return k;
}public V getValue(){return v;}}final static String SPACE=" ";public static TreeMap<Integer,
Integer>mapc(final int[]a){return IntStream.range(0,a.length).collect(()->new TreeMap<Integer,
Integer>(),(res,i)->{res.put(a[i],res.getOrDefault(a[i],0)+1);},Map::putAll);}public 
static TreeMap<Long,Integer>mapc(final long[]a){return IntStream.range(0,a.length).collect(
()->new TreeMap<Long,Integer>(),(res,i)->{res.put(a[i],res.getOrDefault(a[i],0)+
1);},Map::putAll);}public static<T>TreeMap<T,Integer>mapc(final T[]a,Comparator<T>
cmp){return IntStream.range(0,a.length).collect(cmp!=null?()->new TreeMap<T,Integer>(cmp)
:()->new TreeMap<T,Integer>(),(res,i)->{res.put(a[i],res.getOrDefault(a[i],0)+1);
},Map::putAll);}public static<T>TreeMap<T,Integer>mapc(final T[]a){return mapc(a,
null);}public static TreeMap<Integer,Integer>mapc(final IntStream a){return a.collect(
()->new TreeMap<Integer,Integer>(),(res,v)->{res.put(v,res.getOrDefault(v,0)+1);
},Map::putAll);}public static TreeMap<Long,Integer>mapc(final LongStream a){return 
a.collect(()->new TreeMap<Long,Integer>(),(res,v)->{res.put(v,res.getOrDefault(v,
0)+1);},Map::putAll);}public static<T>TreeMap<T,Integer>mapc(final Stream<T>a,Comparator<T>
cmp){return a.collect(cmp!=null?()->new TreeMap<T,Integer>(cmp):()->new TreeMap<T,
Integer>(),(res,v)->{res.put(v,res.getOrDefault(v,0)+1);},Map::putAll);}public static
<T>TreeMap<T,Integer>mapc(final Stream<T>a){return mapc(a,null);}public static<T>
TreeMap<T,Integer>mapc(final Collection<T>a,Comparator<T>cmp){return mapc(a.stream(),
cmp);}public static<T>TreeMap<T,Integer>mapc(final Collection<T>a){return mapc(a.stream());
}public static TreeMap<Integer,List<Integer>>mapi(final int[]a){return IntStream.range(0,
a.length).collect(()->new TreeMap<Integer,List<Integer>>(),(res,i)->{if(!res.containsKey(a[i]))
{res.put(a[i],Stream.of(i).collect(Collectors.toList()));}else{res.get(a[i]).add(i);
}},Map::putAll);}public static TreeMap<Long,List<Integer>>mapi(final long[]a){return 
IntStream.range(0,a.length).collect(()->new TreeMap<Long,List<Integer>>(),(res,i)
->{if(!res.containsKey(a[i])){res.put(a[i],Stream.of(i).collect(Collectors.toList()));
}else{res.get(a[i]).add(i);}},Map::putAll);}public static<T>TreeMap<T,List<Integer>>
mapi(final T[]a,Comparator<T>cmp){return IntStream.range(0,a.length).collect(cmp
!=null?()->new TreeMap<T,List<Integer>>(cmp):()->new TreeMap<T,List<Integer>>(),
(res,i)->{if(!res.containsKey(a[i])){res.put(a[i],Stream.of(i).collect(Collectors.toList()));
}else{res.get(a[i]).add(i);}},Map::putAll);}public static<T>TreeMap<T,List<Integer>>
mapi(final T[]a){return mapi(a,null);}public static TreeMap<Integer,List<Integer>>
mapi(final IntStream a){int[]i=new int[]{0};return a.collect(()->new TreeMap<Integer,
List<Integer>>(),(res,v)->{if(!res.containsKey(v)){res.put(v,Stream.of(i[0]).collect(Collectors.toList()));
}else{res.get(v).add(i[0]);}i[0]++;},Map::putAll);}public static TreeMap<Long,List<Integer>>
mapi(final LongStream a){int[]i=new int[]{0};return a.collect(()->new TreeMap<Long,
List<Integer>>(),(res,v)->{if(!res.containsKey(v)){res.put(v,Stream.of(i[0]).collect(Collectors.toList()));
}else{res.get(v).add(i[0]);}i[0]++;},Map::putAll);}public static<T>TreeMap<T,List<Integer>>
mapi(final Stream<T>a,Comparator<T>cmp){int[]i=new int[]{0};return a.collect(cmp
!=null?()->new TreeMap<T,List<Integer>>(cmp):()->new TreeMap<T,List<Integer>>(),
(res,v)->{if(!res.containsKey(v)){res.put(v,Stream.of(i[0]).collect(Collectors.toList()));
}else{res.get(v).add(i[0]);}i[0]++;},Map::putAll);}public static<T>TreeMap<T,List<Integer>>
mapi(final Stream<T>a){return mapi(a,null);}public static<T>TreeMap<T,List<Integer>>
mapi(final Collection<T>a,Comparator<T>cmp){return mapi(a.stream(),cmp);}public 
static<T>TreeMap<T,List<Integer>>mapi(final Collection<T>a){return mapi(a.stream());
}public static List<int[]>listi(final int[]a){return IntStream.range(0,a.length).mapToObj(i
->new int[]{a[i],i}).collect(Collectors.toList());}public static List<long[]>listi(final 
long[]a){return IntStream.range(0,a.length).mapToObj(i->new long[]{a[i],i}).collect(Collectors.toList());
}public static<T>List<Pair<T,Integer>>listi(final T[]a){return IntStream.range(0,
a.length).mapToObj(i->new Pair<T,Integer>(a[i],i)).collect(Collectors.toList());
}public static List<int[]>listi(final IntStream a){int[]i=new int[]{0};return a.mapToObj(v
->new int[]{v,i[0]++}).collect(Collectors.toList());}public static List<long[]>listi(final 
LongStream a){int[]i=new int[]{0};return a.mapToObj(v->new long[]{v,i[0]++}).collect(Collectors.toList());
}public static<T>List<Pair<T,Integer>>listi(final Stream<T>a){int[]i=new int[]{0};
return a.map(v->new Pair<T,Integer>(v,i[0]++)).collect(Collectors.toList());}public 
static<T>List<Pair<T,Integer>>listi(final Collection<T>a){int[]i=new int[]{0};return 
a.stream().map(v->new Pair<T,Integer>(v,i[0]++)).collect(Collectors.toList());}public 
static String join(final int[]a){return Arrays.stream(a).mapToObj(Integer::toString).collect(Collectors.joining(SPACE));
}public static String join(final long[]a){return Arrays.stream(a).mapToObj(Long::toString).collect(Collectors.joining(SPACE));
}public static<T>String join(final T[]a){return Arrays.stream(a).map(v->Objects.toString(v)).collect(Collectors.joining(SPACE));
}public static<T>String join(final T[]a,final Function<T,String>toString){return 
Arrays.stream(a).map(v->toString.apply(v)).collect(Collectors.joining(SPACE));}public 
static<T>String join(final Collection<T>a){return a.stream().map(v->Objects.toString(v)).collect(Collectors.joining(SPACE));
}public static<T>String join(final Collection<T>a,final Function<T,String>toString)
{return a.stream().map(v->toString.apply(v)).collect(Collectors.joining(SPACE));
}public static<T>String join(final Stream<T>a){return a.map(v->Objects.toString(v)).collect(Collectors.joining(SPACE));
}public static<T>String join(final Stream<T>a,final Function<T,String>toString){
return a.map(v->toString.apply(v)).collect(Collectors.joining(SPACE));}public static
<T>String join(final IntStream a){return a.mapToObj(Integer::toString).collect(Collectors.joining(SPACE));
}public static<T>String join(final LongStream a){return a.mapToObj(Long::toString).collect(Collectors.joining(SPACE));
}public static List<Integer>list(final int[]a){return Arrays.stream(a).mapToObj(Integer::valueOf).collect(Collectors.toList());
}public static List<Integer>list(final IntStream a){return a.mapToObj(Integer::valueOf).collect(Collectors.toList());
}public static List<Long>list(final long[]a){return Arrays.stream(a).mapToObj(Long::valueOf).collect(Collectors.toList());
}public static List<Long>list(final LongStream a){return a.mapToObj(Long::valueOf).collect(Collectors.toList());
}public static<T>List<T>list(final Stream<T>a){return a.collect(Collectors.toList());
}public static<T>List<T>list(final Collection<T>a){return a.stream().collect(Collectors.toList());
}public static<T>List<T>list(final T[]a){return Arrays.stream(a).collect(Collectors.toList());
}public static String yesNo(final boolean res){return res?"YES":"NO";}public static 
String dump(Object obj){String res="";if(obj!=null){Class cl=obj.getClass();String 
cls=cl.getName();if(cls.startsWith("[")){res+="[";for(int i=0;;i++){try{Object o
=Array.get(obj,i);String s=dump(o);if(i>0){res+=", ";}res+=s;}catch(ArrayIndexOutOfBoundsException 
ex){break;}}res+="]";}else if(Collection.class.isAssignableFrom(cl)){@SuppressWarnings("unchecked")final 
Object s=((Collection)obj).stream().map(v->dump(v)).collect(Collectors.joining(", ",
"[","]"));res+=s.toString();}else if(Map.class.isAssignableFrom(cl)){@SuppressWarnings("unchecked")final 
Object s=((Map)obj).entrySet().stream().map(v->dump(v)).collect(Collectors.joining(", ",
"{","}"));res+=s.toString();}else if(Character.class.isInstance(obj)|| Integer.class.isInstance(obj)
|| Long.class.isInstance(obj)|| Float.class.isInstance(obj)|| Double.class.isInstance(obj)|| String.class.isInstance(obj)
){res+=Objects.toString(obj);}else if(Map.Entry.class.isInstance(obj)){res+=dump(((Map.Entry)obj).getKey())
+"="+dump(((Map.Entry)obj).getValue());}else if(Stream.class.isInstance(obj)){@SuppressWarnings("unchecked")
final Object s=((Stream)obj).map(v->dump(v)).collect(Collectors.joining(", ","[",
"]"));res+=s.toString();}else{res+=Stream.concat(Arrays.stream(obj.getClass().getFields()).map(v
->{String name=v.getName();String val;try{Object o=v.get(obj);if(o!=null && v.isAnnotationPresent(Dump.class))
{Dump an=v.getAnnotation(Dump.class);Class ocl=o.getClass();val="{";for(String fn:an.fields())
{try{Field f=ocl.getField(fn);val+=fn+"="+dump(f.get(o))+", ";}catch(NoSuchFieldException 
nsfex){try{@SuppressWarnings("unchecked")final Method m=ocl.getMethod(fn);val+=fn+"="+dump(m.invoke(o))
+", ";}catch(NoSuchMethodException | IllegalArgumentException | InvocationTargetException 
nsmex){}}}if(val.endsWith(", ")){val=val.substring(0,val.length()-2);}val+="}";}
else{val=dump(o);}}catch(IllegalAccessException ex){val="N/A";}return name+"="+val;
}),Arrays.stream(obj.getClass().getMethods()).filter(m->m.isAnnotationPresent(Getter.class)).map(m
->{String name=m.getName();String val;try{Object o=m.invoke(obj);if(o!=null && m.isAnnotationPresent(Dump.class))
{Dump an=m.getAnnotation(Dump.class);Class ocl=o.getClass();val="{";for(String fn:an.fields())
{try{Field f=ocl.getField(fn);val+=fn+"="+dump(f.get(o))+", ";}catch(NoSuchFieldException 
nsfex){try{@SuppressWarnings("unchecked")final Method m1=ocl.getMethod(fn);val+=fn+"="+dump(m1.invoke(o))
+", ";}catch(NoSuchMethodException | IllegalArgumentException | InvocationTargetException 
nsmex){}}}if(val.endsWith(", ")){val=val.substring(0,val.length()-2);}val+="}";}else
{val=dump(o);}}catch(IllegalAccessException | InvocationTargetException ex){val=
"N/A";}return name+"="+val;})).collect(Collectors.joining(", ","{"+obj.getClass().getName()
+": ","}"));}}if(res.length()==0){res="<null>";}return res;}}@Retention(RetentionPolicy.RUNTIME)
public @interface Dump{String[]fields();}@Retention(RetentionPolicy.RUNTIME)public @interface Getter{}static class 
MyScanner{private StringBuilder cache=new StringBuilder();int cache_pos=0;private 
int first_linebreak=-1;private int second_linebreak=-1;private StringBuilder sb=
new StringBuilder();private InputStream is=null;public MyScanner(final InputStream 
is){this.is=is;}public String charToString(final int c){return String.format("'%s'",
c=='\n'?"\\n":(c=='\r'?"\\r":String.valueOf((char)c)));}public int get(){int res
=-1;if(cache_pos<cache.length()){res=cache.charAt(cache_pos);cache_pos++;if(cache_pos
==cache.length()){cache.delete(0,cache_pos);cache_pos=0;}}else{try{res=is.read();
}catch(IOException ex){throw new RuntimeException(ex);}}return res;}private void 
unget(final int c){if(cache_pos==0){cache.insert(0,(char)c);}else{cache_pos--;}}
public String nextLine(){sb.delete(0,sb.length());int c;boolean done=false;boolean 
end=false;while((c=get())!=-1){if(check_linebreak(c)){done=true;if(c==first_linebreak)
{if(!end){end=true;}else{cache.append((char)c);break;}}else if(second_linebreak!=
-1 && c==second_linebreak){break;}}if(end && c!=first_linebreak && c!=second_linebreak)
{cache.append((char)c);break;}if(!done){sb.append((char)c);}}return sb.toString();
}private boolean check_linebreak(int c){if(c=='\n'|| c=='\r'){if(first_linebreak
==-1){first_linebreak=c;}else if(c!=first_linebreak && second_linebreak==-1){second_linebreak
=c;}return true;}return false;}public int nextInt(){return Integer.parseInt(next());
}public long nextLong(){return Long.parseLong(next());}public boolean hasNext(){
boolean res=false;int c;while((c=get())!=-1){if(!check_linebreak(c)&& c!=' '&& c
!='\t'){res=true;unget(c);break;}}return res;}public String next(){sb.delete(0,sb.length());
boolean started=false;int c;while((c=get())!=-1){if(check_linebreak(c)|| c==' '|| 
c=='\t'){if(started){unget(c);break;}}else{started=true;sb.append((char)c);}}return 
sb.toString();}public int nextChar(){return get();}public boolean eof(){int c=get();
boolean res=false;if(c!=-1){unget(c);}else{res=true;}return res;}public double nextDouble()
{return Double.parseDouble(next());}}static abstract class Solver{protected String 
nameIn=null;protected String nameOut=null;protected boolean singleTest=false;protected 
MyScanner sc=null;protected PrintWriter pw=null;private int current_test=0;private 
int count_tests=0;protected int currentTest(){return current_test;}protected int 
countTests(){return count_tests;}private void process()throws IOException{if(!singleTest)
{count_tests=sc.nextInt();sc.nextLine();for(current_test=1;current_test<=count_tests;
current_test++){solve();pw.flush();}}else{count_tests=1;current_test=1;solve();}
}abstract protected void solve()throws IOException;public void run()throws IOException
{boolean done=false;try{if(nameIn!=null){if(new File(nameIn).exists()){try(FileInputStream 
fis=new FileInputStream(nameIn);PrintWriter pw0=select_output();){select_output();
done=true;sc=new MyScanner(fis);pw=pw0;process();}}else{throw new RuntimeException("File "
+new File(nameIn).getAbsolutePath()+" does not exist!");}}}catch(IOException | AccessControlException 
ex){}if(!done){try(PrintWriter pw0=select_output();){sc=new MyScanner(System.in);
pw=pw0;process();}}}private PrintWriter select_output()throws FileNotFoundException
{if(nameOut!=null){return new PrintWriter(nameOut);}return new PrintWriter(System.out);
}}}